Spillway for dams



July 13,19%. Y x

n A Jl F'. VAUGHAN SPILLWAY FOR DAMS Filed May 26, 1925 fnvezzwr Jul] 13, 1925.

LSQZSti JOHN F. VAUGHAN,OF CAMBRIDGE, IVIASSACHUSETTS.

SPILLWAY FOR DAMS.

Application led May 26, i925.

he present invention relates to dams and more particularly to spillways and wasteways for the same.

It is common practice in dam construction to provide for the discharge of surplus water by means ot a spillway extending lengthwise of the dam a sutiicient distance to give the required discharge capacity.

Such a construction ordinarily involves the use of abutments in the body of the dam adjacent the spillway section. The relative cost of such a spillway of concrete or masonry with its abutments is high, and when the dam is ot earth may constitute a large proportionof the cost ot the entire dam, especially where a considerable length Ot spillway is required.

It is one of the objects of the present invention to provide a spillway construction which shall have a greatly increased etiective discharge length relative to its width measured lengthwise of the dam as compared with prior constructions, thus making it possible to obtain the required length ot spillway where there would be insutlicient space it'or the ordinary spillway across the stream, and also making it pos sible to increase the discharge capacity to such ran extent that the normal pond level may be raised without, however, raising the maximum level.

.lt is another object of the present invention to provide a spillwayand wasteway which may be constructed at a relatively low cost, owing to the fact that a much less expensive type of construction may be employed; and further, on account of the short length of the body or" the dam occupied by the spillway and wasteway section, a greater proportionate length of regular dam structure may be used, which, in the case of ear h dams, affords opportunity for large savings.

Stillanother object is to so construct the spillway that the energy ot the waste water will be largely dissipated and liability ot damage to the wasteway and to the stream below will be lessened.

Other objects are to provide a spillway and wasteway which may be protected from the weather and 'from liability of freezing, and further, which will clear itself of ice, logs, or other similar materials.

lith these objects in view the Vpresent invention consists of the structures and combinations, of Structures hereinafter de- Cil Serial No. 32,915.

scribed and more claims.

In the accompanying drawings which illustrate what is now considered to be the preferred form oiE the present invention, Figure l is a top plan view of a transverse section ot earth dam provided with my improved spillway and wasteway construction; Fig. 2 is a vertical section of the saine transversely of the dam; F ig. 3 is a vertical transverse section of the spillway on lines 3*;3 of Fig. 2 looking in the direction ot' the arrows; Fig. 4 is a vertical section of the wasteway on lines 4-4 ot' Fig. 2 looking in the direction ot the arrows; and 5 is a vertical section transverselv of the dam showing a modii'ied construction.

The dam illustrated in the drawings is oi the conventional earth type having the front sloping tace l, the rear sloping" tace 9., and the flat top portion 3. rlhe spilt way and the wasteway which in the drawings are shown as integrally constructed of concrete, consist of a relatively narrow deep structure extending' from the front iace l ot the dam upstream into the pond or reservoir and downstream through the body ot the dam and back face 2. The spillway portion, indicated generally by the reference character 5, comprises the side walls 6 converging upstream in horizontal plan, as shown in Fig. l, and joined at their upstream ends by the end wall 'i'. These side walls 6 rise from the horizontal foundation or base S (see Fig. 3), slichtly diverging to form a structure substantially V or rather U-shaped in vertical cross-section, the tumble bay at the bottom ot the spillway being rounded for a purpose later to be described. The end wall 7 risingfrom the front end of the base 8 is inclined upstream for the greater portion ot its height, the extreme top part, however, being vertical as shown in Fig. 2, and entending well above the top surfaces or crests 9 of the sides ofthe spillway over which crests the waste water flows. The purpose of such extension is to prevent the flow of water over the end wall 7 thus avoiding a plunging concentration or ein cess of flow at the end of the spillway with the resulting piling up of the overt'alling` stream, a depression in the water surface in the tumble bay where it strikes, and a standing wave further down stream..

particularly deiined in the with the sp'illway,extending itroin the rear end rot the latter through the body ln'order to reinforce and strengthen the side Walls ot the spillivay, buttresses or abutments 1l are formed at intervals alongthe cuter surfaces oft the sides 6, anddepending` diaphragm Walls l2 are provided in line With such buttresses and extending downwardly from the base 8 into the earth formation. These buttresses and diaphragm walls have the 'further function ol preventing creepage of Water along the.

14 are provided" which are located in line with the buttresses ll. st'ruts, which are of inverted `J-shape, are shed with steel to protect them from damage The tops of the by falling ice,rlogs, vor` other material in the Waste Water.

The-Wasteway, shown generally by the reference character 15, is :termed integrally the the or dam. Y Like the spillway, it comprises sloping side Walls 17, braced from one. other by thestruts 18, which have'their.

Astream faces tI-shaped and protecively shod with steel.

. ln certain localities,A and -under cert-ain conditions, it may be. necessary to Weatherproof or otherwise protect the spillivay and ufasteivay, as for example, ',froin'treezin 'n the extreme cold oit the northern.latin-idea. Accordingly, a closure or root 2O may be provided,as shown in Figs. 2, 3 and 'which covers the spillivay and Wasteivay with the exception o'vthe extreme downstream end. rlfhis closure issupported over the spillxvay by means ot the 'trout ivall 7 and piers 2l rising` iroinrthe crests ot the-sidewalls 6. On the Wasteway the roof or closure rests directly upon the tops of the side Walls l?.

ln orderto close thel entrance and exit opening` for the Wasteivay they are provided with swinging' gates hung upon the-horizontal pivots` and automatically opening by the pressure ot the Water. These gatcs'QQ at the spillu'ay open inwardly to permitthe Water to flow over the crests oi the side Walls 6 of the spillyvay. The gate 243 at the downstream end ofthe Wasteway .opens outwardly ftopermit the discharge voit-the Waste Water.

Byprovidingthese automatic closures #for the spillivay and Wastevvay, the liability oi3 the vspillivay and ivastevvay being choked or closed ice is greatly reduced, it not 'enavoided, since the temperature Within che bony oit the dani Will remain relatively highl provided the tree circulation of air is pr vented.

ln Fig. 5 is shoivn a modiiied construction in which, instead ot providing a root or cove 'tor the entire spillway and ivastevvay, a hori'fzontal diaphragm 25 is provided which not only takes the place of one row of struts tor bracingthe side Walls 17 from one another, but which alsoprevents thev torinaY tion et ice on the bottoni of the spilhvay. it, for any reason, the passage or tunnel beneath the diaphragm should become choked, the Water is free to flow over the top `oit the diaphragm.

ltvvivill be noted that my improved spillway construction extending from the tace oi the dani upstream into the pond provides a in'aximunioi" spillway length' for a minimum ot Width tor l the spillway and Wastevxay, as measured lengthwise of Ythe dam. Thus ahigher normal pond level may Vbe safely employed With theconsequent advantages of a higher stratum of Water, yet Without using'- flash-boards orA gates, either manually or poweriopeiated or automatic.

My improved spil'livay is of .relatively cheap ceinstruction since thel usual long;` niasonary spillivay may be shortened and the volume et inasonary reduced. and rei'ilaced byy relatively less expensive earth lill, and the bracing ot one Wall from the other permits relatively thin curtain walls to be employed Without impairingthe strength of the structure.

Furthermore, by :conforming the inner surtaces of the,spillivay'crestsI tothe natural curvature otl the nap of the overflow ot water, and by roundingthe hottoniot Athe tumble bay, the vvaste Water Ail'oivs over the ojiipesed vv V tliespillivay in smooth, even streams or sheets. which are brought into direct impact with each other, thereby absorbing to a large degreethe kinetic energy ot the 'falling Water and-permitting a rela tively slow tloiv throughreand out ot the ivasteivay, thus avoiding the objectionable erosive effects ot a high velocity discharge.

ln-the preferred construction the spille ay is substantially V-shaped in horizontal plan, thus providing a progressively greater' den stream capacity to takecare ol the progressivelvgreater amounts of Waste vvater to be handled. Furthermore, both the spillivay and the ivasteivay are il-shaped in vertical cross-section,- thus tending to be sel'tclearing ot obstructions by providing greater pio portionate capacity for the upper thanrthe lower portions thereof'.

' lllhil'e in the drawings I have shown what l consider to be the prefer-red' construction. it is to ,be understood' that inyinvention isnot necessa ily lil 'd thereto ,exceptv ,vliere *sov specifically defined. iii-the claims; cat

Hal

be embodied in other format-ions and 'constructions. For example, the wastevay is illustrated as extending upward to the surface ot the top and downstream slope ot the dam, but this is not essential, it being only necessary that the wasteway extend upward sulliciently to provide a conduit ot the necessary capacity.

Having thus described the invention, what is claimed is:

l. The combination with a dam, of a spillway :tor the same comprising spaced, opposed walls which extend upstream from the face of the dam and over which the water flows in opposing streams, struts between the opposed walls, and a conduit connected with the spillway and extending through the dam for the water flowing over the spillway.

2. The combination with a dam, of a spillway for the same comprising opposed walls which extend upstream from the tace ot the darn and over which the water flows, struts between the opposed walls, and a conduit connected with the spillway and extending through the dam to discharge the water flowing over the spillway.

3. The combination with a dam, of a spillway for the same comprising a spillway wall which extends upstream from the face of the dam and over which the water flows,

a second wall which extends upstream and from which the spillway wall 1s spaced to form a water discharge passage thereber tween, struts between the two walls, and a conduit connected with the spillway and extending through the dam for the waste water flowing over the spillway.

4f. The combination with a dam, of a spillway comprising opposed walls over which the water flows, extending upstream from the tace of the dam and converging in plan view, struts between the walls, and a conduit connected with the spillway and extending through the dam for the water flowing over the spillway.

5. The combination with a dam, of a spillway comprising walls over which the water tlows, extending upstream from the face of the dam and upwardly diverging in vertical cross-section, and a conduit connected with the spillway and extending through the dam for the water iowing over the spillway.

6. rlhe combination with a dam, of a spillway comprising opposed walls over which the water flows, extending upstream from the face of t-he dam, converging in Yplan and upwardly diverging in vertical cross-section, struts between the walls, and a conduit connected with the spillway and extending through the dam for the water flowing over the spillway.

7. The combination with a dam, of a narrow wasteway extending through the dam, the sid-es of the wasteway projecting upstream trom the face of the dam to form a spillway.

S. The combination with a dam, of a narrow dam, the sides projecting upstream from the tace ot the dam to form a spillway, and compression members between the sides.

9. The combination with a dam, ot' a narrow wasteway extending through the dam and upstream from the tace ot' the dam to form a spillway, a root over the spillway spaced therefrom to provide an opening tor the flow of water over the spillway, and swinging gates for said opening.

l0. The combination with a dam, of a iarrow wasteway extending through the dani, the sides of the wasteway projecting upstream to form a spillway, struts between the sides ot the wasteway and spillway, the struts having a V-shaped face, and metal shoes for protecting said faces.

ll. The combination with a dam, of a spillway for the same comprising opposed side walls over the crests ot which the water flows, the walls extending upstream from the face of the dam and being spaced to form a narrow passage for the discharge of the waste water, an end wall joining the side walls and rising above the crests of the latter to prevent the discharge of waste water over the end wall, and a conduit connected with the spillway and extending through the dam to discharge the water flowing over the spillway.

l2. 'lhe combination with a dam, ot a narrow wasteway extending through the dam, with its sides projecting upstream from the tace of the dam to form the sides of a spillway over the crests ot' which the water tlows, an end wall joining the side walls and rising above the crests of the side walls, supports rising from said crests, a roof carried by the end wall and the supports, inwardly swinging gates pivoted upon horizontal axes and tending t-o close by gravity the inlet openings between the crests and the roof, a root for the wasteway, and an outwardly swinging gate pivoted on a horizontal axis and tending to close by gravity the outlet end of the wasteway.

18. rllhe combination with a dam, of a spillway for the same extending upstream from the face of the dam and comprising side walls, a base extending laterally beyond the side walls, lateral buttresses rising from the base and supporting the side walls, and struts between the side walls.

14. The combination with a dam, of a spillway for the same extending upstream from the face of the dam and comprising a base, side walls rising from the base within its lateralmargins and outwardly inclined, curtain walls extending downwardly from wasteway extending through the inwardly swinging gates tending to close 10 said openings, ay roof Jor the Wasteway, and an outwardly swinging gate normally tendlngA to close the discharge end of the Wasteway.

In testimony whereof I have signed my 15 naine to this speeication.

JOHN F. VAUGHAN. 

